This invention generally relates to electrical equipment for housing electrical devices such as switches and outlets, and particularly to electrical box extensions.
Electrical boxes are commonly used to provide electrical service at convenient locations within buildings. The electrical boxes are commonly formed of plastic or metal and are usually securely fastened by screws or nails to the framework of a structure being prepared for electrification. In newly constructed buildings, the open face of the electrical box, within which an electrical device such as an outlet or switch will be mounted, is usually flush with the surface of the wall or ceiling in which it is installed.
When buildings are renovated or restored or otherwise modified from their original wall and ceiling surfaces, it is common for renovators to lay down new sheet stock such as sheet rock, paneling, and the like, over the existing ceilings or walls. This process of layering causes the existing electrical boxes to become recessed within the built-up wall by the thickness of the new sheet stock. A need for extension therefore occurs when the box or mud ring has been placed and then tile, brick or some other wall covering is added thereby causing the screw mounts for plugs and/or switches to be recessed within the wall.
To solve this problem, box extenders of several different types have been developed. One type relies on a friction fit to hold the box extender in the existing electrical box. This extender does not provide a secure attachment to the existing box and may allow an attached electrical device to slide further within the box as the extender will slide based on an external force.
Another type of extender consists of an extension having walls of approximately the same configuration as the existing box and of fixed depths of extension. The extender is available in several depths to accommodate several different sheet stock thicknesses.
Although there are several depths available, the depth is not continuously variable resulting in an inability to consistently provide a depth extension bringing the existing box flush with the outer wall surface.
Another type of extender includes a body portion having at least one wall and open faces. The extender includes side flanges having holes that align with brackets that are connected to the electrical box. This extender is difficult to use and install as brackets must be firmly attached to the electrical box and then two screws are used to attach each flange of the extender to the electrical box.
There remains a need to extend the electrical box with a minimal number of parts that provide ready height adjustment while maintaining mechanical and structural soundness and electrical connectivity including ground, and thereby compensate for add-ons to a wall that cause depth to be added between the box or ring and the outer wall.